GMC Pickup C2500 (1985-2000) org/ Wiring diagrams

1-2 SHIFT SOLENOID 2-3 SHIFT SOLENOID 29 30 VSS LO (GROUND) VSS HI (SIGNAL) ANTI-LOCK BRAKES SYSTEM AUTOMATIC TRANSMISSION BLK WIRE BLK/WHT WIRE BLU/WHT WIRE BRAKE FUSE 18 BRN WIRE BRN/WHT WIRE CRUISE CONTROL DK BLU WIRE ECM 1 FUSE ECM-B FUSE ELECTRONIC BRAKE CONTROL MODULE ENGINE CONTROLS ENGINE COOLANT TEMPERATURE SENSOR (TOP RIGHT FRONT OF ENGINE) FLUID TEMP SENSOR FRONT WHEEL LOCK FUEL INJECTORS, IGNITION CONTROL MOUDULE, IGNITION COIL FUEL PUMP, OIL PRESS SWITCH/ SENDER, FUEL PUMP RELAY GRY WIRE GRY/BLK WIRE HI LO HOT AT ALL TIMES HOT IN HOT IN OFF, RUN OR START HOT IN RUN OR START HOT IN RUN OR START I/P FUSE BLOCK (UNDER LEFT SIDE OF DSAH) GAUGES FUSE 4 I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) INLINE GENDER ADAPTOR INSTRUMENT CLUSTER LT BLU WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE MALFUNCTION INDICATOR LAMP ORG/ WIRE PNK PNK WIRE PNK WIRE PPL PPL DATA LINK CONNECTOR (UNDER LEFT SIDE OF DASH) PPL/WHT WIRE PRESS CTRL SOLENOID RED WIRE RED/BLK WIRE REV, LO RUN WIRE TAN WIRE TCC PWM SOLENOID TCC/ABS/ CRUISE SWITCH THROTTLE POSITION SENSOR (MOUNTED TO SIDE OF THROTTLE BODY) TRANS FUSE 20 TRANS RANGE PRESSURE SWITCH ASSEMBLY TRANSFER CASE CIRCUIT TRANSFER CASE, AXLE SWITCHES UNDERHOOD FUSE/RELAY CENTER (LEFT REAR OF ENGINE COMPT) VEHICLE CONTROL MODULE (LEFT SIDE OF ENGINE COMPT) VEHICLE SPEED SENSOR (LEFT SIDE OF YEL WIRE YEL/BLK WIRE

1-2 SHIFT SOLENOID 2-3 SHIFT SOLENOID A/T ISS SENSOR VSS IN SENSOR GROUND SENSOR GROUND APP 1 SIGNAL IN ACCELERATOR PEDAL POSITION MODULE (PART OF ACCELERATOR PEDAL) APP 3 SIGNAL IN SENSOR GROUND A/T ISS SENS LO AUTOMATIC TRANSMISSION BLK WIRE BLK/WHT WIRE BLU/WHT WIRE BRAKE FUSE 18 BRN WIRE BRN/WHT WIRE DK BLU WIRE DK GRN WIRE ECM-B FUSE ELECTRONIC BRAKE CONTROL MODULE PPL ENGINE CONTROLS SYSTEM ENGINE SHUTOFF SOLENOID, FUEL SOLENOID EXTERIOR LIGHTS FUEL PUMP, OIL PRESS SWITCH/ SENDER, FUEL PUMP RELAY GAUGES FUSE 4 GRY WIRE GRY/BLK WIRE HI LO HOT AT ALL TIMES HOT IN HOT IN RUN OR START I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) INLINE GENDER ADAPTOR INSTRUMENT CLUSTER LT BLU WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE MALFUNCTION INDICATOR LAMP ORG/ WIRE PNK PPL WIRE PNK WIRE POWERTRAIN CONTROL MODULE (RIGHT SIDE OF DASH NEAR BLOWER MOTOR) PPL PPL DATA LINK CONNECTOR (UNDER LEFT SIDE OF DASH) PPL PNK PNK WIRE PPL PRESS CTRL SOLENOID PPL/WHT WIRE RED WIRE RED/BLK WIRE RUN WIRE STOP/HAZ FUSE 1 TAN WIRE TAN/WHT WIRE TCC PWM SOLENOID TRANS FLUID TEMP SENSOR TRANS FUSE 20 TRANS RANGE PNK PNK REV, LO WIRE TRANS RANGE PRESSURE SWITCH ASSEMBLY TRANSFER CASE CIRCUIT TRANSFER CASE CIRCUIT PNK WIRE TURN/ HAZARD SWITCH, CHIME MODULE VEHICLE SPEED SENSOR (LEFT SIDE OF VEHICLE SPEED SENSOR BUFFER (RIGHT SIDE OF DASH) WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

1-2 SHIFT SOLENOID 2-3 SHIFT SOLENOID 29 30 VSS LO (GROUND) VSS HI (SIGNAL) ANTI-LOCK BRAKES SYSTEM AUTOMATIC TRANSMISSION BLK WIRE BLK/WHT WIRE BLU/WHT WIRE BRAKE FUSE 18 BRN WIRE BRN/WHT WIRE CRUISE CONTROL DK BLU WIRE ECM 1 FUSE ECM-B FUSE ELECTRONIC BRAKE CONTROL MODULE ENGINE CONTROLS ENGINE COOLANT TEMPERATURE SENSOR (TOP RIGHT FRONT OF ENGINE) FLUID TEMP SENSOR FRONT WHEEL LOCK FUEL INJECTORS, IGNITION CONTROL MOUDULE, IGNITION COIL FUEL PUMP, OIL PRESS SWITCH/ SENDER, FUEL PUMP RELAY GRY WIRE GRY/BLK WIRE HI LO HOT AT ALL TIMES HOT IN HOT IN OFF, RUN OR START HOT IN RUN OR START HOT IN RUN OR START I/P FUSE BLOCK (UNDER LEFT SIDE OF DSAH) GAUGES FUSE 4 I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) INLINE GENDER ADAPTOR INSTRUMENT CLUSTER LT BLU WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE MALFUNCTION INDICATOR LAMP ORG/ WIRE PNK PNK WIRE PNK WIRE PPL PPL DATA LINK CONNECTOR (UNDER LEFT SIDE OF DASH) PPL/WHT WIRE PRESS CTRL SOLENOID RED WIRE RED/BLK WIRE REV, LO RUN WIRE TAN WIRE TCC PWM SOLENOID TCC/ABS/ CRUISE SWITCH THROTTLE POSITION SENSOR (MOUNTED TO SIDE OF THROTTLE BODY) TRANS FUSE 20 TRANS RANGE PRESSURE SWITCH ASSEMBLY TRANSFER CASE CIRCUIT TRANSFER CASE, AXLE SWITCHES UNDERHOOD FUSE/RELAY CENTER (LEFT REAR OF ENGINE COMPT) VEHICLE CONTROL MODULE (LEFT SIDE OF ENGINE COMPT) VEHICLE SPEED SENSOR (LEFT SIDE OF YEL WIRE YEL/BLK WIRE

BLK WIRE BLK/RED WIRE BRN WIRE CONVENIENCE CENTER FRONT HEATED SEATS FUSE HEATED SEAT SW SIG HIGH/LOW SIG HOT AT ALL TIME HOT IN RUN RR HVAC FUSE 5 I/P FUSE BLOCK INDICATOR LMP FEED LEFT FRONT HEATED SEAT MODULE (UNDER LEFT FRONT POWER SEAT) LEFT FRONT HEATED SEAT SWITCH LEFT FRONT LEFT FRONT SEAT CUSHION SEAT TEMPER- ELEMENT ATURE SENSOR LEFT FRONT SEAT BACK ELEMENT LEFT FRONT SEAT CUSHION LT BLU WIRE LT BLU/BLK WIRE OFF OFF LO ORG/ WIRE PNK/BLK WIRE PPL RIGHT FRONT HEATED SEAT MODULE (UNDER RIGHT FRONT POWER SEAT) RIGHT FRONT HEATED SEAT SWITCH RIGHT FRONT SEAT BACK ELEMENT RIGHT FRONT SEAT BEALT SWITCH RIGHT FRONT SEAT CUSHION ELEMENT RIGHT FRONT SEAT TEMPER- ATURE SENSOR SIG ENABLE UNDERHOOD FUSE/RELAY CENTER YEL WIRE

BLK WIRE CONVENIENCE CENTER HOT AT ALL TIMES I/P FUSE BLOCK LEFT FRONT POWER LUMBAR SEAT SWITCH LEFT FRONT POWER LUMBAR SUPPORT MOTOR LEFT LUMBAR SOLENOID ORG/ WIRE PPL PWR-ACCY CIRCUIT BREAKER RIGHT FRONT POWER LUMBAR SEAT SWITCH RIGHT FRONT POWER LUMBAR SUPPORT MOTOR RIGHT LUMBAR SOLENOID TAN WIRE

BLK WIRE CIG LTR FUSE 13 CONVENIENCE CENTER HOT AT ALL TIMES I/P FUSE BLOCK LEFT FRONT POWER LUMBAR SEAT SWITCH LEFT FRONT POWER LUMBAR SUPPORT MOTOR LEFT LUMBAR SOLENOID ORG/ WIRE PPL RED WIRE RIGHT FRONT POWER LUMBAR SEAT SWITCH RIGHT FRONT POWER LUMBAR SUPPORT MOTOR RIGHT LUMBAR SOLENOID SUBURBAN, UTILITY ONLY TAN WIRE W/ SPLIT BENCH SEAT W/O SPLIT BENCH SEAT

AUTOMATIC TRANSFER CASE CONTROL MODULE AUTOMATIC TRANSFER CASE ONLY AUTOMATIC TRANSFER CASE SELECT SWITCH AUXILIARY AUXILIARY TEMPERATURE HIGH BLOWER DOOR MOTOR MOTOR RELAY AUXILIARY BATTERY AUXILIARY BATTERY RELAY (LEFT REAR OF ENGINE COMPT) AUXILIARY HEATER AND A/C CONTROL LOGIC MODULE AUXILIARY HEATER AND A/C CONTROL MODULE (FRONT) AUXILIARY HEATER AND A/C CONTROL MODULE (REAR) AUXILIARY MEDIUM BLOWER MOTOR RELAY BLK WIRE BLK/RED WIRE BLU WIRE BRAKE FUSE 18 BREAKOUT) BRN WIRE COLUMN HARNESS BREAKOUT) CONVENIENCE CENTER CROSSBODY HARN, 20 CM FROM SDM BREAKOUT) CRUISE CONTROL MODULE (GAS ONLY) CRUISE CONTROL SWITCH CRUISE FUSE 6 ELECTRONIC BRAKE CONTROL MODULE FROM BREAKOUT TO GROUND AT LEFT SIDE FRAME RAIL, NEAR CROSSMEMBER) FROM IGNITION SWITCH (DIAGRAM 3 OF 6) FROM UNDERHOOD FUSE-RELAY CENTER (DIAGRAM 1 OF 6) FROM UNDERHOOD FUSE-RELAY CENTER (DIAGRAM 3 OF 6) FRONT AXLE ACTUATOR FRONT HEATED SEATS FUSE FUSE 24 FUSIBLE LINK GAS, BASE MODELS DIESEL GAS, OTHERS MODELS HTR A/C FUSE 12 HVAC CONTROL MODULE I/P FUSE BLOCK LEFT FRONT FENDER) LEFT FRONT HEATED SEAT MODULE LEFT REAR HEATED SEAT MODULE LEFT REAR HEATED SEAT SWITCH MODE DOOR MOTOR MOTOR RELAYS) ORG/ WIRE REAR HEATED SEATS FUSE REAR HEATER REAR HEATER W/ W/ REAR CARGO LIFT- HEATER DOORS GATE ONLY RECIRCULATION TEMPERATURE DOOR DOOR MOTOR MOTOR RED WIRE RESTRAINT SWITCH BREAKOUT) RIGHT FRONT HEATED SEAT MODULE RR HVAC FUSE 5 SEATS FUSE STOP LAMP SWITCH SUBURBAN, UTILITY ONLY TRANSFER SPARE CASE POWER SWITCH SOURCE UNDERHOOD FUSE-RELAY CENTER UPPER LEVEL VEHICLE CONTROL MODULE (GAS ONLY) W/ REAR DEFROST

AUXILIARY POWER CENTER (CENTER OF DASH) BLK WIRE CICUIT BREAKER CUSTOMER INSTALLED OPTIONS FROM PWR WDO CIRCUIT BREAKER (DIAGRAM 3 OF 6) FROM RIGHT BATTERY (DIAGRAM 1 OF 6) FUSE FUSE BLOCK 3 FUSE BLOCK 5 FUSE FUSE GENERATOR MEGA FUSE ORG/ WIRE PNK WIRE POLICE PACKAGE RED WIRE RELAY RELAY/ FUSE RIGHT BATTERY WHT WIRE YEL WIRE

AUDIO ALARM MODULE (ON CONVENIENCE CENTER) BLK WIRE BLK/WHT WIRE DIESEL GAS GAUGES FUSE 4 GRY WIRE HOT AT ALL TIMES HOT IN PARK OR HEADLIGHT HOT IN RUN, BULB TEST OR START I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) ILLUM FUSE 14 INSTRU- MENT CLUSTER SAFETY BELTS INDICATOR KEY-IN WARNING BUZZER SWITCH LEFT FRONT DOOR JAMB SWITCH LIGHTS ON INPUT POWER INPUT KEY-IN WARNING LT GRN WIRE ORG/ WIRE PNK IGNITION ON INPUT WIRE PNK WIRE SEAT BELT INPUT GROUND FASTEN BELTS OUT SEAT BELT SWITCH (ON DRIVER'S SEAT BELT BUCKLE) STOP/HAZ FUSE 1 SUPPLEMENTAL RESTRAINTS SYSTEM TAN WIRE YEL WIRE

BATTERY INPUT BLK WIRE BLK/WHT WIRE BODY CONTROL MODULE (IN CENTER CONSOLE) BRN WIRE CTSY FUSE 3 DK BLU WIRE GAUGES FUSE 4 GROUND FASTEN BELTS OUT HEADLAMP, PANEL DIMMER SWITCH HOT AT ALL TIMES HOT IN RUN OR START I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) INSTRU- MENT CLUSTER KEY-IN WARNING BUZZER SWITCH LEFT DOOR JAMB SWITCH LT GRN WIRE ORG/ WIRE PKLPS FUSE 9 PNK WIRE POWER DISTRIBUTION SYSTEM SAFETY BELTS INDICATOR SEAT BELT SWITCH (ON DRIVER'S SEAT BELT BUCKLE) SUPPLEMENTAL RESTRAINTS SYSTEM TAN WIRE WHT WIRE YEL WIRE